Oats: the breakfast that turns on you

Oats are the default breakfast in most camps. Cheap, easy, filling in the way people mean when they say filling, and eaten by more fighters more mornings than any other single food.

They are also the food most likely to be sitting in you on the morning of a weigh-in, for a reason worth understanding rather than just accepting.

What beta-glucan actually does

The relevant thing in oats is beta-glucan, a soluble fibre that forms a viscous gel with water. Almost everything oats are known for traces back to that viscosity.

The effect on the stomach has been measured directly. In a randomised crossover trial, 22 healthy adults were given 25 grams of available carbohydrate either as a beta-glucan-enriched oat bread or as a whole-wheat control, with gastric emptying tracked by ultrasound.

Eighteen minutes does not sound like much. It is a single meal, in a controlled setting, at a modest carbohydrate load. A fighter eating a large bowl of porridge every morning is running that delay daily, on a much larger portion, and it compounds across the days when nothing is supposed to be left in him.

The part I had wrong

The obvious next claim is that oats keep you full, and it is the reason most people give for eating them in a deficit.

The evidence for that is weaker than the mechanism suggests.

So the mechanism is real and the outcome does not reliably follow. Slowing the stomach is not the same as making somebody eat less later, and the literature on this is mixed rather than settled.

That matters for how you should think about oats in camp. They are a good breakfast for practical reasons: cheap, quick, easy to eat in quantity, tolerated by most people. Eating them because they will control your appetite is a weaker argument than it sounds, and if you are relying on that and finding yourself hungry by 11, the food is not failing you.

The claim was.

When they become the problem

Everything in your digestive tract on the morning of a weigh-in is weighed with you. That is the whole of it, and the full accounting is in gut content and the last 3 days.

Oats contribute to that in three ways at once.

• The fibre itself is residue. It leaves slowly, and a food that leaves slowly accumulates.
• The beta-glucan gel holds water while it sits there, and that water is inside you.
• And the porridge was made with water. Two or three hundred millilitres go into the pan and go in with the bowl. Nobody counts that, and it is the most obvious part.

Which produces the same reversal that governs rice: the qualities that make oats a good breakfast in week six are precisely the qualities that make them the wrong one in week 12.

The trap

Porridge is the food a fighter is least likely to remove.

It is breakfast, it is habit, and it feels virtuous. When the low-residue phase starts he takes out the salad, the wholegrain bread, the beans and the raw vegetables, and he keeps the bowl he has eaten every morning for 2 years because removing it never occurs to him.

Then the last kilogram does not move, and he looks at water, at sweat, at the sauna. Not at the bowl.

It is never the fighter being careless. It is the opposite: he is being careful about everything he has been told to be careful about, and porridge was never on that list.

What to do in ordinary camp

Use them, for the practical reasons rather than the marketed one.

Steel-cut and rolled behave similarly for a fighter's purposes. Instant sachets are usually smaller portions with added sugar, which changes the arithmetic if you are counting and nothing more.

Oats carry more protein than most grains and still not enough to make a protein meal. Three quarters of a cup dry gives you something around 10 grams, well under the 20 to 40 gram range a feed should be aiming at.

They belong alongside eggs, dairy or a protein powder rather than instead of them.

Two individual qualifications. Some people bloat considerably more on oats than on rice, and if that is you, the general argument does not apply to your gut. And on genuinely hard training days, when the objective is getting carbohydrate in rather than feeling full, a food that slows the stomach is working against you.

The switch, and when to make it

At the start of the low-residue phase, not the night before the scale.

This is the error that catches people who already know the rule. Fibre eaten on Tuesday is still moving through on Thursday, and a decision taken on Thursday evening cannot change Friday morning.

The switch belongs 3 to 5 days out, at the same moment the rest of the low-residue plan starts.

What replaces it is unglamorous and works: white rice, white bread or a plain roll, plain pasta, or eggs with a refined carbohydrate alongside.

None of those is the breakfast you would choose in week six.

All of them are right in the last days.

After the scale

Not in the first hours.

The refuelling window needs fluid and fast carbohydrate moving in quickly, and oats are the opposite of quick by a measured margin.

Putting them in early is choosing the slowest available option at the moment speed is the entire point.

By the evening meal, or by breakfast the following morning if the fight is later, they are fine again. The restriction ends when the scale does.

On fight day

No.

Everything above applies, plus the fact that high-intensity work slows gastric emptying further by itself. A food that already sits longer, eaten before a warm-up that will slow things down again, is a poor choice at the one moment when being wrong is most expensive.

The gluten question

Oats do not contain gluten.

They are, however, frequently grown in rotation with wheat and processed on shared equipment, which is why coeliac athletes need oats specifically labelled gluten free rather than ordinary ones.

That is the standard position of coeliac organisations rather than a cautious opinion.

A very small number of people with coeliac disease react to avenin, the protein in oats itself, even when the oats are certified pure.

That is rare, and it is a clinical question rather than something to self-diagnose.

For everybody else the whole issue is irrelevant. Cutting oats on the assumption that they contain gluten is one of the more common versions of removing a food group for no reason, and the way to settle whether you actually have a problem is in gluten, lactose and the fighter who cut a food group for no reason.

How much, in practical terms

Most people underestimate what they are eating here, because oats expand dramatically. Sixty grams dry looks like almost nothing in the pan and fills a large bowl once cooked.

If you are tracking, weigh them dry. Cooked weight depends entirely on how much liquid went in and is not comparable between two mornings.

And the protein column is the point of the earlier section. Even 80 grams of oats, which is a substantial breakfast, gives you around 10 grams of protein.

That is a third of a feed, which is why the bowl needs something with it.

Overnight oats, and whether they are different

Soaking oats overnight rather than cooking them changes the texture and very little else that matters here. The fibre is the same, the beta-glucan is the same, and the effect on the gut in the final days is the same.

What does change is convenience, and for somebody fitting camp around a job that is not a small thing. A container prepared the night before removes the most common reason breakfast gets skipped, which is that there was no time.

Two practical notes. Oats soaked in milk carry the milk's protein and calories, which improves the protein problem described above. And the volume of liquid is part of what you are eating, which matters in the final days when everything liquid counts.

In an away camp

Oats travel better than almost any other food a fighter eats. They need no refrigeration, they weigh little, and a bag of them solves breakfast in a hotel where the alternative is a buffet you did not choose.

Hot water from a kettle is enough. It will not be good porridge and it will be breakfast, which in an unfamiliar country with an unfamiliar kitchen is worth more than good porridge.

Hotel breakfast oats are usually instant sachets with added sugar. Not a disaster, and worth knowing rather than assuming you got what you would have made.

The bowl you forgot to remove

• Eat them in camp because they are cheap, quick and easy, not because you have been told they control hunger. The mechanism is real and the appetite claim does not consistently hold.
• Take them out at the start of the low-residue phase, not at the end of it.
• Count the water they were cooked in. It goes in with the bowl.
• Do not put them back in the first hours after the scale, and do put them back the following morning.
• If you removed them over gluten without ever being tested, test it properly. There is a decent chance you have avoided a good breakfast for a decade over an assumption.